Redundant Air Supply

[asmfish]

Hey guys I’m looking to invest in a redundant air supply (pony bottle) I’m single tank diver who just started diving locally where a lot of the dive boats require one. Does anyone have any recommendations on what size I should be looking to purchase. I don’t do wreck penetration dives or any cave diving. And greatest depth would be around 120 feet.

Thanks.

 

[caruso]

Now here's a topic that's never been discussed on this forum before.

/sarcasm off

Ok since you asked, it's generally agreed that a 19cf pony bottle will suffice for most recreational divers who dive to as much as 130'. That size pony bottle can be carried in luggage and isn't too inconvenient to lug around with the rest of your dive gear while providing sufficient gas for most divers to make it to the surface if they have an OOA situation at maximum recreational depths.

Next size down is about 13cf and it's not really that much smaller for all practical purposes and now you're getting into a grey area where it might not provide enough gas.

Then there's the "Spare Air" self contained "mini bottle" system. Some divers (such as me) will tell you any extra air is better than no air, and yet others will tell you that if you use a Spare Air you're going to die it's only a matter of when.

 

[BoltSnap]

When I dove in the NY/NJ area, wrecks in recreational depths mostly, I used 40cuft tank for a pony bottle. I take the worst case scenario depth wise and potential reason for running out of air, stuck at the bottom because of fishing lines or similar add the time for the safety stop and possibly a buddy in need of air and 40cuft is minimum for me.

 

[caruso]

I see you're in NY, so am I. Curious what dive boats you're looking to go out on? Most are gone. I was just looking to see what charter schedules are posted and they're slim pickings.

2 years ago, I picked up an 18 footer and got out on the LI sound and did about a dozen dives including one of the artificial reefs with wrecks at about 60'. As well as some jetties and rocky reefs that are not accessible from shore because the rich folks own all the property. Always looking for company.

 

[W W Meixner]

Attached photos shows some potential options for you...

I have an AL 30/27/19...the harnesses are DIY...the butterfly snap hooks/sheathed S/S straps are DGX...

The harness assembly on the 27 is interchangable between the 27 and the 30...the small harness assembly on the step is for the 19...

If your not into DIY...DGX has pre-fabbed harness assemblies with all the hardware...

Their house brand deco/stage/bailout fully assembled reg sets are an excellent buy...

Hope this helps you...

Best...

Warren

 

[doctormike]

Awesome! Another NY area local diver... come dive with us, if you are near NYC.

I think that the 40 is such a common standard in our area (where people use them for deco and bailout), that unless you are really planning on flying a lot with your pony, you will find it easier to buy a 40 used (and sell later if necessary). Plus, when you are slinging the bottle, the difference between a 19 and a 40 isn't very noticeable, and I think that the 40 actually hangs better.

Plus - more gas! Always a good thing (see the last 6,000 threads on this topic).

 

[noj3333]

@caruso and @doctormike...

If there's ever interest in setting up a charter I'd be interested and could drive down...

 

[doctormike]

We have a bunch of charters, although they are mostly sold out at this point... but I'm at the NJ shore lots during the season

Dive Schedule

 

[Diver below 83]

View attachment 514600 View attachment 514601 Attached photos shows some potential options for you...

I have an AL 30/27/19...the harnesses are DIY...the butterfly snap hooks/sheathed S/S straps are DGX...

The harness assembly on the 27 is interchangable between the 27 and the 30...the small harness assembly on the step is for the 19...

If your not into DIY...DGX has pre-fabbed harness assemblies with all the hardware...

Their house brand deco/stage/bailout fully assembled reg sets are an excellent buy...

Hope this helps you...

Best...

Warren

Wow they are a lot closer in size then I expected. How much larger is a 40 next to a 30?

 

[RyanT]

The 40 cf tank is almost 6" longer than the 30 cf. Both are 5.25" diameter. To the uninitiated, that extra 6" makes the 40 look a lot bigger and more unwieldy than a 30. It's nearly the same length as an AL 80 or an HP 100 that you would have on your back. In reality, 40 is no more difficult to clip on or swim with than a 30. The 19 is definitely a more compact tank being shorter and skinnier than even the 30.

Here's a link to the dimensions.

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